Blow molding is a manufacturing process widely used to create hollow thin-wall plastic objects such as bottles, cases, containers, and bellows.

A typical blow molding process begins with a heated hollow thermoplastic tube, also known as preform or parison. The plastic tube has a hole in one end, allowing compressed air to enter. It is then inflated into the closed chamber of a divided mold to conform to the shape of the mold cavity. The molded plastic will be left to cool and harden. Once released from the mold, the plastic part can be post-processed to have the holes rimmed or residues trimmed.

Not all plastics are suitable for blow molding. THe most frequently used materials in blow molding are

The products manufactured by blow molding, although limited to hollow shaped plastics, are widely used in many industrial fields and everyday lives. The following are the products that see a lot of blow molded parts: